Hartstein revealed on Twitter in November that he had been informed that the decision not to renew his Formula One contract had been taken by Jean Todt and the president of the FIA Medical Commission. However, having originally said it is "not down to me to know" the reasons for the change, Hartstein has today taken to Twitter once again to voice his anger and declare that he is set to challenge the FIA's decision.
"It's taken a while, but I am righteously pissed off," Hartstein wrote. "I might launch a crusade to get some answers, or get my f***ing job back, or let the world know what's REALLY going on on the medical side of the FIA. Understand this: I am NOT bitter or sad. I am seriously angry. And that's bad.
"Not sure how or when, but there's dark clouds a-gatherin'. This is gonna be a f***ing blast!"
Hartstein later added: "Ok now we all need to be patient. I'll tweet my usual blather for a few weeks then we'll see where we're at." ESPN F1